Sewing machine



June 23, 1925.

- A. F. FIFIELD SEWING MACHlNE Filed July 20, 1921,

2 Sheets-Sheet 1 INVENTOR momma BY 1 TTORNEY n lilllli iii L: I

WITNESS June 23, 1925.

- A;F.F""ELD SEWING mAcH;NE

Filed July 20, 1921 2 Sheets-Sheet 2 INVENTOR I Fi .MMWM

wn' SSE S f I I TTORNEY'I Patented June 23, 1925.

UNITED STATES 1,542,865 PAT-VENT, OFFICE.

ALBERT E. FIFIELD, 0F NEWARK, NEW JERSEY, AssIsNoR 'To- THE SINGER MANU-EAcTuRIne COMPANY, 0E EL ZABETH, NEW JERSEY, A CORPORATION OF NEWJERSEY.

SEWING MACHINE.

1 Application filed July 20, 1921. Serial No. 486,215,

To all w ham it may. concern: I

Be it known that I, ALBERT F. FIFIELD, a citizen of the 'United States,residing at Newark, in the county of Essex and State of New Jersey, haveinvented certain new and useful Improvements in Sewing Machines, ofwhich the following is a specification, reference being had therein tothe accompanying drawings.

This invention relates to an improvement in sewing vmachines providedwith stopmotion devices for controlling the operation of thestitch-forming mechanism, and has for its object to provide simple andeffective interlocking means whereby the stop-motion may not be operatedto start the machine while a work-engaging element is retracted fromoperative position and whereby the latter may not be operated While thestop mot-ion is in running position. V

lVhile certain features of the present improvement are not confined toassociation with any particular type of stop-motion, it is especiallyadapted for employment in connection with that form ofstop-motioncomprising, fixed and loose pulleys with a stopping cam attached to androtating with the fixed pulley and a swinging controlling lever carryinga belt-shipper and a stopping element in the form of a spring-pressedplunger-bar cooperating with the stopping cam in arresting thestitch-forming mechanism at the end of a cycle of operation of themachine.

In its preferred form, the machine is provided with a presser-liftinglever fulcrumed upon the bracket-arm and with a rock-shaft sustainedupon and longitudinally of said bracket-arm and having at one end acrankarm connected with said lifting lever and at the opposite end astop-arm normally retracted from but adapted when the lifting lever isoperated to swing into the range of movement of the stop-motioncontrolling lever to obstruct its movement to operative position andconsequent shift of the powerbelt from the loose to the fastpulley anddisengagement of the plunger-bar from the stopping cam. As the stop-armand stopmotion controlling lever have intersecting paths of movement,and their normal positions are closely adjacent each other, each iseffectively locked against operative movement as soon as the other hasperformed an initial portion of an operative movement, so

that neither of the interlocking parts can perform even a partialmovement when the other is retracted from initial position.

In the accompanying drawings, Fig. 1 is a rear side elevation of aSinger flat-button sewing machine constructed in substantial accordancewith my patent No. 1,226,963 of May 22, 1917, and embodying the presentinvention. Fig. 2 is a front end elevation of the same with the forwardportion of the bracket-arm omitted to expose the parts rearward of thesame, certain ofwhich are represented in section. Fig. 3 isa plan of theinterlocking parts embodying the pres- ..ent invention, with the sewingmachine frame and certain other parts represented in dotted lines.

. As represented, the machine is constructed with a frame comprising thecylinder-bed or work-arm lfrom the rear end of which rises the standard2 from which laterally extends the hollow overhanging arm 3 terminatingin the head 4:. Journaled within and longitudinally of the arm 3 isthemainshaft 5 from which is derived through usual operative connectionsthe reciprocating movements of the needle-bar 6 carrying the needle 7.

The machine is shown with a well-known form of jogging work-holdercomprising the sliding bar 8 carrying at its forward end thework-supporting plate 9, and near its rearward end the block 10 in whichis pivoted the spring-depressed arm 11 carrying the upper presser orwork-clamping member 12. Jogging movements are imparted to thework-holder by well-known means including the cam13 having theface-groove 14: I

adapted to be entered by a roller-stud upon the rock-lever 15communicating its vibratory movements to the slide-bar 8 through theadjustable link 16 and other suitable connections.

The work-holder arm 11 carries the usual post 17 terminating in. across-member adapted to engage a lateral member 18 of the block 19 fixedupon-the lower end of the lifter-bar 20.having adjacent its upper endthe collar 21. Interposedbetween the collar 21 and the top of the head iis the forward end of the controlling lifting lever 22 mounted by meansof the fulcrum-pin 23 upon the bracket 24 secured upon the bracket-arm3. v

The stop-motion mechanism ofthe present mounted within the swingingstop-lever 29 fulcrumed at 30 upon a bracket of the standard 2. Thelever 29 carries the belt-shipper arm 31. Mounted upon the pivotal pin32 of the bracket 33 is the angular shift-lever 34for tilting thestop-lever 29 in opposition to its spring 35 to shift the driving beltfrom the loose to the tight pulley and disengage the plunger-bar 28 fromthe stopping cam27.

The stop-lever is detained in running position by means of thecatch-lever 36 mount ed upon the frame by means of the fulcrumscrew-stud 37 and adapted to be tripped for disengagement of thestop-lever by means of the tripping stud 38 carried upon the inner faceof the cam-wheel '13.

Mounted in bearings 39 and 40, secured respectively to the bracket-arm 3and standard 2, is the rock-shaft 41 extending length- :wise of the arm3 and parallel with the main-shaft 5. Fixed upon the forward end of therock-shaft 41 is the crank-arm 42 pivotally connected to the lower endof the link 43 whose apertured upper end embraces the screw-stud 44tapped into a lateral boss when in'stopping position, as represented inthe drawings. The swinging stop-lever 29 and stop-arm 46 are so mountedthat each is movable into the range of movement of the other, so thatwhen one is moved from normal retracted position the other is lockedagainst corresponding movement.

Th -machine being at rest, the operator lifts the upper work-clampingmember or work-presser 12 to admit the work by tilting the lifting lever22 through the usual treadle connection, thereby rockingthe shaft 41 andshifting the stop-arm 46 into the dotted line position represented inFig. 2, thus obstructing the starting movement of the stoplever 29 andthe premature starting of a stitching operation. The work having beeninserted and the presser lowered, the stop-arm 46 is returned to itsinitial full line position of Fig. 2, and the stop-lever 29 isthereafterfree to be shifted forwardly to start the main-shaft and thestitclnforming mechanism, as represented in full lines in Fig. 3. Inthis position of the parts the operative movement of the stop-arm 46 isobstructed by the stop-lever 29, thereby preventing the actuation of thelifting lever 22 and raising of the work-presser 22 to open theworkholder prematurely, It will thus be seen that the initial raising ofthe work-presser will insure against premature starting of the stitchingmechanism, While the shift of the stop-lever to start the stitclrforming mechanism in operation will insure against the inopportuneopening of the work-holder, the interlocking means accomplishing thisresult according to the present improvement having direct and positiveconnections with the parts which they thus control.

The employment of a rock-shaft carrying the stop-arm and operativelyconnected with the lifting mechanism affords a simple and effectiveinterlocking means for the purpose described, while the location of therock-shaft upon the bracket-arm insures compactness and neatness ofappearance.

'VVhile the stop-lever 29 and stop-arm 46, in the present embodiment,vibrate or reciprocate in curved paths about their respective fulcra, itis evident that in certain aspects of the present improvement the natureof their reciprocatory' movements isinot material.

Having thus set forth the nature of the invention, what I claim hereinis 1. In a sewing machine, in combination, stitch-forming mechanism, a-main-shaft, tight and loose belt-pulleys on said mainshaft, a manuallyoperated belt-shipper lever, a work-clamp, a manually operatedclamp-opening lever, a rock-shaft parallel to said main-shaft andconnected to said clamp-opening lever, and a stop-arm on said rock-shaftarranged to move into the path of and block movement of said beltshipperlever to running posit-ion when the work-clamp is open. 1

2. In a sewing machine, in combination, a stop-motion comprising acontrol lever manually shiftable to starting position to efifectconnection of the machine with a source of power, a worleclamp, manuallyoperated means for opening the work-clamp, and a stop-arm connected tosaid manually operated means and pivotally mounted to swing on an axisparallel to the plane of manual movement of said stop-motion controllever, said stop-arm being arranged to move into the path of and blockmovement of said stop-motion control lever tostarting position when thework-clamp is open.

3. A sewing machine having a frame including a bed and overhangingbracket-arm, StltGll-fOlllllDQ, mechanism lncorporated in said frame, awork-clamp, a manually operated'lever fulcrumed on said bracket-arm andconnected to open said work-clamp, a stop-motion device for thestitch-forming mechanism including a belt-shipper lever manually shiftable to starting position to eifect connection of the machine to a sourceof power a rook-shaft journaled on said bracket-arm and having itsopposite ends disposed respectively, adjacent the clamp opening andbe1t-shipper levers, means connected to the clamp-opening lever forrocking said shaft, and a stop-arm mounted on said shaft so as to moveinto the path of and block movement of the belt-shipper lever to 1running position When the Work-clamp is open.

In testimony whereof, I have signed my name to this specification.

ALBERT F. FIFIELD.

